2016 started off way hotter than 2015. A sudden jump like this is called a step change. If you expect we'll now cool off to our previous decadal average, forget that. We've "leveled up".

The current warming surge amounts to what’s called a step change — a practically instantaneous shift in our planet’s climate.

This sudden shift in temperature has arrived because of a confluence of events: Long-term global warming, the multiyear effect of El Niño, and extreme weather — including persistent heat waves at the regional scale.

According to a five-year prediction from the Met Office, global temperatures may fall slightly over the next year or two, as the El Niño wanes and temporarily cooler ocean temperatures associated with La Niña take hold. But global warming will make that respite brief: 2018, 2019 and 2020 will likely be warmer than 2015, and the warming trend is expected to continue long after that. Sixteen of the 18 years that followed the last big El Niño (1997-98) were warmer than 1997. [emphasis mine]

Step changes also happen in other climate issues, such as the rate of sea level rise. Sudden jumps in the rate of melt indicate a tipping point was passed, and new self-reinforcements have kicked in.

Doubling times in non linear events often don’t fit a pure exponential curve — instead tending to follow a series of spikes and recessions with major transitional events coming at the end of any ‘curve.’ [emphasis mine]

Our path ahead: major transitional events kicking us into new regimes of change we'll hate.

The past three month temperature jump seems like nonlinear change, according to Gwynne Dyer.

IF YOU spend a lot of time talking to scientists about climate change, there's one word you'll hear time and time again, and yet it's hardly ever mentioned in the public discussion of climate change. The word is "non-linear".

As for the frightening acceleration in the warming in the past three months, that has no precedent in any El Nino year, or indeed in any previous year. … Could this be non-linear change, an abrupt and irreversible change in the climate? Yes. And if it is, how far will it go before it stabilises again at some higher average global temperature? Nobody knows.

… the warming is now accelerating in an unprecedented way.

Based on the first three months, 2016 is predicted to average 1.32°C above preindustrial.

NASA GISS head — Gavin Schmidt — in a recent tweetestimated that 2016 would fall into a range near 1.32 C above the 1880-1899 average that NASA uses for its preindustrial baseline. By comparison, 2015... hit 1.07 C above the 1880-1899 average. [emphasis mine]

As a result,2016 will likely have jumped by about a quarter of a degree Celsius in a single year.

Regime shifts are abrupt, substantial and persistent changes in the state of natural systems. [emphasis mine]

This change wasn't recognized until now

...due to a paucity of long-term time series that are maintained and sampled in the same consistent way over decades, and a compartmentalization of science with insufficient communication between different disciplines.

For inclusion in the analysed database, continuous data sets needed to be within the period 1946 to 2012 and start by 1980 at the latest.

A clear shift emerged from the data, accounting for 49% of total variance, in 1987. "The second component, which accounts for 12% of the total variance, is correlated, for example, with the Arctic Oscillation, North Atlantic Oscillation, Arctic sea-level pressure and zonal wind."

... a fundamental shift in the climate system took place at this time. It is clear that rapidly increasing temperature is central to the shifts, with rising concentrations of greenhouse gases contributing to a net warming of global climate since the late 1970s…

Temperature appears to be the main forcing factor behind the shift:...

Independent of our study, there is substantial evidence that changes in the heat structure of the world are profoundly affecting regional climate variability, the cryosphere, terrestrial systems, sea level, ocean hydrodynamics and the biogeochemistry, ecosystems and living resources of the world.

What is the trigger that initiated the sudden increase in temperature ...?

Our results based on CMIP5 and statistical modelling indicate that a combination of warming from natural and anthropogenic forcing was responsible as a rebound from the cooling that followed the El Chichón eruption together with a reduction in stratospheric aerosols, although the relative contribution of each forcing factor is still unclear.

The major volcanic eruption of El Chichón in 1982 was responsible for an estimated cooling of 0.2–0.3 °C per decade, offsetting anthropogenic warming and resulting in relatively small global mean temperature trends in the early 1980s. ... recovery from the climatic impacts of the eruption, including a reduction in stratospheric aerosol concentrations, led to a natural warming, reinforcing anthropogenic warming and producing a rapid increase in global mean temperature on a higher level than before the eruption ... As a result, the global climate shifted to a warmer state in just a few years, setting in motion a cascade of responses in natural systems.

[order changed, emphasis mine]

In sum, El Chichón's eruption temporarily masked the growing cumulative impact of greenhouse gases for five years. When that cooling faded, the sudden warming reinforced anthropogenic warming, with cascading temperature-driven changes.

A small excerpt from the mind-numbing charts.

Vertical lines denote regime shift years (P ≤ 0.05), coloured throughout the paper to reflect the ‘1980s period of interest’ (1983–1990): 1984 (blue), 1985 (green), 1986 (orange), 1987 (red), 1988 (brown), 1989 (purple), 1991 (pink as a lagged effect); grey solid lines mark the earlier and later regime shifts (1976 and 1996), and grey dashed lines other significant shift years outside the 1980s. Horizontal lines mark the longest test-period with a significant result. Triangles (coloured as per the shift year) point up or down to indicate the direction of a significant trend before or after the shift year:...

The locations of these high latitude temperature anomalies relate to abnormal jet stream patterns.

... warm-air slots running from Tropics to Pole appear to remain intact in the Northeastern Pacific and over Central Asia in the Northern Hemisphere during early Summer. Meanwhile, an odd Southern Hemisphere warm-air slot appears to have developed during June in the region of the Southeastern Pacific.

The reign of record hot months in 2016 continues, with last month claiming the title of hottest July on record globally, according to data released by NASA on Monday. This July was also the hottest month on record for the world.

... 2016 is still well on its way to upsetting last year as the hottest year on record. ..., there is still a 99 percent chance 2016 will take the top slot.

Schmidt said he expects July will be the last record hot month of this year as the residual heat from an exceptionally strong El Niño dies away. Though El Niño itself was declared over in June, global temperatures tend to lag by about two to three months.